Control apparatus



Sept. 23, 1947. LEE, 25 2,427,794

CONTROL APPARATUS Q 5 Sheets-Sheet 1 Filed Dec. 31, 1945 LER PITCH TGOVERNOR THROTTLE INVENTOR .[EEZZ F I6. I

IGNITION CONTROL p 1947- 1.. LEE, 2D 2,427,794

CONTROL APPARATUS Filed Dc. 51, 1943 5 Sheets-Sheet 2 FIG. 5

so 206 I2 L. LEE, 2D CONTROL APPARATUS Filed Dec. 31, 1945 5Sheets-Sheet 3 Sept. 23, 1947.

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CONTROL APPARATUS Filed Dec. 31, 1943 5 Sheets-Sheet 4 Sept. 23, 1947.

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CONTROL APPARATUS Filed Dec. 31, 1943 5 Sheets-Sheet 5 FIG. 8

T0. PROPELLER PITCH (0 1 w GOVERNOR To DECREASE SPEED FIG. 9

TO GARBURETOR AIR TEMPERATURE To CONTROL TORQUE BALANCING FLAP CONTROLIN V EN TOR.

Patented Sept. 23, 1947 CONTROL APPARATUS Leighton Lee, H, Meriden,Conn, assignor, by mesne assignments, to Niles-Bement-Pond Company, WestHartford, Conn, a corporation of New Jersey Application December 31,1943, Serial No. 516,407

33 Claims. 1

The present invention relates to control apparatus for internalcombustion engines.

The invention is described herein as applied to an internal combustionengine used on aircraft, although it may be applied to other internalcombustion engines. The internal combustion engines now in common use onaircraft require many manually operated control devices to regulatetheir operation. These devices usually include the throttle, the mixturecontrol, the ignition timing control, the propeller pitch or enginespeed governor, and the carburetor air temperature control. In additionto these usual controls, other accessories may be provided such as waterinjection valves, fuel selector valves, etc. In order to obtain the bestengine operation at any given power output, all these control deviceshave to be adjusted to particular settings. The setting of each of thesecontrol devices demands attention from the pilot, who also has manyother duties to perform besides controlling the engine. As a result thepilot usually must neglect the setting of one or more of these controldevices with the result that the emciency of the engine is impaired.

It i therefore an object of the present invention to provide controlapparatus for simultaneously positioning a plurality of control devicesof an internal combustion engine in order to maintain optimum conditionsof engine operation. Another object of the present invention is toprovide a control system in which a single lever operable by the pilotor other member of the aircraft crew, determines the setting of aplurality of devices for controlling conditions relating to theoperation of the engine.

Another object is to provide a system of the type described in which themanually movable lever may selectively be used either to control motormeans for setting all the control devices or to manually position thethrottle only.

A further object of the present invention is to provide an improvedmotor control system in which a single motor is used to perform a numberof different functions. Another object is to provide, in such a system,an improved clutch means driven by the motor for connecting it to a loaddevice.

A further object is to provide improved clutch means for connecting amotor to a plurality of load devices.

Other objects and advantages of the present invention will becomeapparent from a consideration of the appended specification, claims anddrawing, in which Figure 1 is a somewhat diagrammatic illustration,partly in section, of a control system for an internal combustion engineembodying the principles of my invention,

Figure 2 is a, cross-sectional view taken along the line 22 of Figure 1,looking in the direction of the arrows,

Figure 3 i a cross-sectional view of a clutch illustrated in Figure 1,taken along the line 3-3 of Figure 1 and looking in the direction of thearrows,

Figure 4 is an elevational view of the clutch mechanism illustrated inFigure 3, taken along the line 4-4 in Figure 1,

Figure 5 is an elevational View of a switch contact structure takenalong the line 5-5 in Figure 1, and looking in the direction of thearrows,

Figure 6 is a graphical illustration of the relationship between variousconditions of engine operation which may be obtained by the use of myinvention,

Figure 7 is another graphical illustration of other conditions of engineoperation obtainable thru the use of my invention,

Figure 8 is a somewhat diagrammatic illustration of an interlockingmechanism which may be used in the control system of Figure 1, and

Figure 9 is an extension of a portion of Figure 1, illustrating certainadditional controls which may be connected to that system.

Referring to Figure 1, there is shown an arm 10 which is adapted forattachment thru suitable linkage to the pilots control lever. The lowerend of arm [0 is fixed to a shaft I2. A series of arms 14, I6, l8 and 20are pivotally mounted on the shaft l2, and each of these arms is adaptedfor attachment to a control device associated with the engine. Asindicated by the legends in the drawing, the arm 14 may be connected tothe ignition timing control, the arm [6 may be connected to the fuel andair mixture control, the arm [8 may be connected to the propeller pitchor engine speed governor and the arm 20 may be connected to thethrottle. The arms l4, l6 and I8 are also preferably connected tomanually operable levers under the control of the pilot, or other crewmember.

The right end of shaft l2, as it appears in Figure 1, carries anenlarged portion 22 having a groove 24 cut in its surface. A collar 26surrounds the enlarged portion 22 of shaft l2 and is restrained fromrotation with the shaft 12 by means not shown. A set screw 28 isthreaded thru the collar 26 so that its inner end rides in the groove24. The construction is such that as 3 shaft I2 is rotated, the collar26 is moved lengthwise on the enlarged portion 22 of shaft I2.

An extension 36 of the collar 26 insulatingly carries a pair of contacts32 and 34 which cooperate with a contact member 36 insulatingly carriedby a belloWsj38. The bellows .38 is sealed. This bellows and themechanism which operates the contacts 32 and 34 is mounted in a housing46 whose interior are connected by a conduit 42 to the intake manifoldof the internal combustion engine being controlled. The bellows 38therefore responds to the absolute manifold pressure.

As an alternative mode of operation, the interior of bellows 38 and theinterior of housing 46 may be connected respectively to a pair ofpressures whose difference indicates the quantity of air flowing to theengine for combustion purposes. In place of the'mechanism shown somewhatdiagrammatically in the housing-46, I preferto use a device of the typeshown and claimed in my copending application Serial No. 514,022, filedDecember 13, 1943.

A disc 44, of insulating material, is fixed on the shaft I2 for rotationtherewithand carries a pair of contact fingers 46 and 48 on its oppositesurfaces. Another insulating disc56 is attached to ahub-52 which carriesthe throttle arm 26, The disc 56 supports a pair of contacts 53 and 54which cooperate with the contact 46 carried by disc 44. A thirdinsulating contact disc 56 is rotated about the shaft I2 by the hub of abevel gear 58 driven by a mechanism-to be described in detailhereinafter. The disc 56 carries a pair of contacts 66 and 62 whichcooperate with the contact finger 48 carried by disc 44.

A hub 64 is attachedto the shaft I 2, and is pivotally connected to alink 66. The other end of link 66 is pivotally attached to a hub 68rotatable about a clutch shaft 16. Also rotatable about clutch shaft 16is an elongated sleeve or hub 12. The sleeve 12 carries an arm 14connected by a link 16 to the hub 52 of throttle arm 29. The

sleeve 12 may be connected to the hub 68 for rotation therewith by aclutch mechanism generally indicated at '18, shown in-its engagedposition.

A gear I I4 is rotatable about the sleeve 12. The gear II4 may be fixedon the sleeve 12 by means of a clutch mechanism 6. The gear II4 mateswith a gear II 8 fixed on a shaft I20.

Hubs 86, 82 and Marc also rotatably mounted on the shaft 16,and areconnected thru links 86, 88 and 96 respectively, with the control arm I4, I6 and I8. The hubs 80, 82 and 84 may be connected by means ofclutches 92, 94 and 96, respectively, with cam follower arms 98, I66 andI62. The cam followerarm 98 is not completely shown in the drawing, butthe cam follower mechanism associated with it is substantially the sameas those asosciated with arms I66 and I62, which are shown in detail. a

The arms I66 and I62 carry at their respective ends pins I64 and I66.The pin I64 and I66, respectively, move in slots in disc cams I68 and II6 fixed on the shaft I26. The pins therefore serve as cam followers.

The clutch mechanisms 18, 92, 94, 96 and H6 are all generally similar.The clutch mechanism 92 is shown in detail in-.Figures 3 and 4.Referring to those figures,it may be seen that the cam follower arm 98is provided witha'central recess I22, in which'a key I24 movesunder'the'influence of a compression spring I26 and a cam surface I28formed on the shaft 16. As may be seen in Figure 1, the key I24 isgenerally T shaped, and

4. is provided with lateral extensions I21. The extensions I21 arealined with shoulders I29 in the hub 86. Each shoulder I 29 is notched,as at I36, so that the extensions I21 may be received in the notches.

Referring to Figures 3 and 4, it may be seen that when the clutch shaft16 is rotated from the position shown, the key I 24 then engages the lowpoint of the cam surface I28, against which it is forced by the springI26. The extensions I21 then move into engagement with the notches I36,if they are angularly alined, and the arm 98 is then looked to the hub86 so that the two move together. When the parts of the clutch are inthe positions shown in Figures 1, 3 and 4, the hub 86 and the arm 98 arefree to move angularly with respect to each other. If the extensions I21and the notches I36 are not angularly alined, then the key I 24 cannotengage the low point ofcam I28 when the shaft 16 is rotated 180 from theposition shown. Instead, the extensions I21 then ride on the shouldersI29. Then if by rotation of hub -86 or arm 98 the notches I36 becomealined with extensions I21, the extensions move into the notches underthe influence of spring I 26, thereby locking hub 86 and arm 98together.

The shafts H2 and I26 are both driven by the same electrical motorgenerally indicated at I32. The motor I32 consists of two concentricrelatively rotatable members I34 and I36. For the sake of convenience,the members I34 and I36 will be hereinafter referred to as the statorand rotor respectively, altho inthe construction shown, the stator I34is not stationary. The rotor I36 is connected to the shaft I26 thru areduction gear indicated schematically at I31. The stator I34 carries anexternal gear I 38 which drives the shaft II2 thru a reduction geargenerally indicated at I46. Sli rings I42, I43 and I44 are mounted onthe outside of statorJ 34, in order to conduct electric current to thewindings on the stator. Altho no means are shown for conducting currentto the windings on the rotor I36, it will be readily understood thatsuch means may be provided if the motor is of a type requiring it.

Motor I32 is provided with two windings which when energized causeopposite reactions between the stator and rotor. The winding which, whenenergized, causes clockwise rotation of shaft I26, as viewed from theright end, is hereinafter referred to as the clockwise winding.Similarly, the winding which causes counterclockwise rotation of shaftI26 is referred to as the counterclockwise winding. These windings arenot individually shown in the drawing, for the sake of simplicity. Ofcourse, the clockwise winding causes counterclockwise rotation of thestator, as viewed from the right end, and the counterclockwise windingcauses clockwise rotation of the stator. The clockwise winding isconnected to slip ring I44 and the counterclockwise winding is connectedto slip ring I42.

Abrake band I46 is also attached to the outside of stator I34. A brakeI41 is biased to engage brake band I46 and prevent movement of statorI34. An electromagnet I48 is effective when energized to move brake I41away from band I 46 and thereby release stator I34.

The cam shaft II2 drives the gear'56 and disc 56 thru bevel gears I56and I52, a shaft I54 and a bevel gear I56 which mates with gear 58.

In addition to gear II8, the shaft I26 drives a worm I58 thru a pair ofbevel gears I66 and I62. The worm I58 cooperates with a sector wormwheel I64 attached to the clutch shaft .16.. The worm wheel I64 isprovided with teeth on its periphery over a sector which extendsslightly more than 180. The remainder of the periphery of the worm wheelis recessed so that it does not engage the worm I68.

The clutch shaft 16 also carries a disc I66, which is notched as at I68.A tension spring I16 is mounted between a stationary pin HI and a pinI13 on disc I66 to bias the clutch shaft 16 to an angular position inwhich the toothed sector of the worm wheel I64 engages the worm I58. Anelectromagnetic latching mechanism I12 is provided to hold the disc I66and the clutch shaft 16 in a different angular position wherein the wormI58 is free of the worm wheel I64. The electromagnetic latchingmechanism I12 includes a latch member attached to its armature I14,which is biased by a spring I16 to a position wherein the latch memberis free of the disc I66. When the electromagnetic mechanism I12 isenergized, the latch member is moved downwardly into engagement with theperiphery of disc I66. Then when the disc I66 is rotated to a positionsuch that notch I68 is aligned with the latch member, the latter dropsinto the notch and thereafter retains the disc I66 in that angularposition. The upper end of armature I14 engages the tip of a switchfinger I18 which moves between a pair of stationary contacts I66 andI82, being self-biased to engage contact I82.

A master switch I84 is provided for turning the system on and off, and asingle-pole, doublethrow selector switch I86 is provided for selectingdifferent modes of operation of the system.

Operation When the parts are in the positions shown in the drawing, thevarious control arms I6, I4, I6, I8 and 26 are independently movable tooperate the control devices connected thereto. Manipulation of the leverat this time causes operation of the throttle lever 26. The mechanicalconnection between these two may be traced from lever I6 thru shaft I2,hub 64, link 66, hub 66, clutch 18, sleeve 12, arm 14, link 16, hub 52and throttle arm 26.

The system may be operated to act as a follower mechanism so that thevarious control levers I4, I6, I8 and 26 are driven to angular positionscorresponding to that of the manual con trol lever I6. This mode ofoperation of the system will be hereinafter referred to assemi-automatic operation. In order to secure this mode of operation, theselector switch I86 is moved to the position illustrated in full linesin the drawing, and the switch I84 is closed. This completes a circuitfor energizing the latching electromag net I12 and another circuit forenergizing motor I32. The circuit for electromagnet I12 may be tracedfrom the upper terminal of a battery I88 thru switch I84, a conductorI66, electromagnet I12, and ground connections I6l and I62 to the lowerterminal of battery I88. The circuit for energizing motor I32 may betraced from the upper terminal of battery I88, thru switch I84, aconductor I64, switch finger I18, contact I86, a conductor I96, aconductor I98, slip ring I42, the counterclockwise winding on statorI34, 'a slip ring I43, and ground connections I66 and I62 to the lowerterminal of battery I68. The winding energized thru this circuit is theone which causes shaft I26 to be rotated in a counterclockwise directionas viewed from the right end in Figure 1. Therefore bevel gear I62 isdriven clockwise as viewed from below in Figure 1 and the worm I68engages worm wheel I64 driving the latter and the shaft 16 clockwise.The clockwise rotation of disc I66 initially releases some of thetension in spring I16, but after pin I13 reaches its bottom centerposition, the spring I16 is stretched until the pin I13 reaches its topcenter position. After that, the spring I16 aids the motor in causingfurther clockwise rotation of the disc I66. When the worm I58 reachesthe end of the toothed sector of worm wheel I64, which occurs after thepin I13 passes top center, the spring I16 causes further clockwiserotation of disc I66 until the latch member drops into the notch I66,whereupon the disc I66 is effectively locked against further rotation.Since the worm I66 does not then engage the worm wheel I64, the motorI32 i free to rotate the shaft I26 in either direction without causingany movement of shaft 16.

The rotation of shaft 16 thru in the operation just described results ina disengagement of clutch 18 and makes possible the engagement ofclutches 62, 64, 96 and H6 whenever the extensions I21 of any of thelatter clutches become angularly alined with the associated notches I36.The disengagement of clutch 18 breaks the mechanical connection betweenthe manual control lever I6 and the throttle arm 26. The angularalinement of the extensions I21 and notches I36 of the clutches 92, 64and 96 may be accomplished by manually moving the notched hubs 86, 82and 84 by means of the levers I 4, I6 and I8, respectively, until thenotches and extensions become aligned, whereupon the clutches engage andfurther manual movement of the levers becomes impossible. In the case ofclutch II6, however, the angular alinement of the clutch notches andextensions is accomplished by the rotation of gear II4 on the sleeve 12.The gear H4 is rotated whenever the control system .calls for anoperation of the throttle, and when once started, continues until thethrottle has been moved to the desired position. Therefore, whenrotation of gear H4 starts at a time when the notches and extensions ofclutch I I8 are not aligned, those parts become aligned at some point inthe first revolution of gear II4, the clutch H8 then engages the gear II4 with sleeve 12, and thereafter the throttle is driven as required bythe control system. The mechanical connection between the rotor I36 ofmotor I32 and the throttle arm 26 may be traced thru shaft I26, gears H8and H4, clutch H6, sleeve 12, arms 14, link 16, hub 52 and arm 26. Whenthe control arms I4, I6 and I8 are connected to their respective cams,they are operated by stator I34 of motor I32. In the case of the arm I8,the connection may be traced from stator I34 thru gears I36 and I46,shaft II2, cam II6, cam follower pin I66, arm I62, clutch 66, hub 64 andlink 66 to control arm I8.

When the armature I14 moves the latch member downwardly into the notch68, the switch finger I18 is simultaneously disengaged from contact I86and moved into engagement with contact I82. This completes an energizingcircuit for motor I32 in which the position of contact 68 with respectto the contacts 66 and 62 determines the direction of operation ofstator I34. The angular position of contact 48 corresponds to that ofthe manual control lever I6 and the angular positions of contacts 66 and62 correspond to the angular position of the cam shaft II2. If theangular position of cam shaft H2 is displaced with respect to theangular position of shaft I2 so that the contact 48 engages either ofthe con.-

tacts 68 and 62, then the motorlis energized to drive the stator in adirection so'thatthe disc 56 circuit is broken.

Whenever either of the circuits controlled by contact 48 is completed,theelectromagnet I48 is energized by a circuit to be traced hereinafter,thereby disengaging brake I41 from brake drum I46 and allOWlng statorI34 to rotate. Since the rotor I36 is at this time connected to thethrottle thru the reducing gear-I31, the load on the stator I34 isrelatively lighter than that on the rotor and energization of the'motorwindings at this time therefore causes rotation of the stator I34 ratherthan of the rotor I36.

For example, if the position of contact 48 with respect to disc 56 isthat illustrated in Figures 1 and 5, then an energizingcircuit for themotor is completed which may be traced from the upper terminal'ofbattery I88, thru switch I84, conductor I94, switch finger-I18, contactI82, a conductor 280, relay winding 282, a conductor 204, contact 48,contact 68, a conductor'286, a conductor 208, conductor E88, slip ringI42, the

counterclockwise winding on stator I34, slip ring I43 and groundconnections I99 and I 92 to the lower terminal of battery I88. Thiswinding is the same one whose energization previously caused rotation ofshaft I 20 in a counterclockwise direction, as viewed from the rightend. Therefore energization of this same winding now causes the rotationof stator I34 in a clockwise direction. This causes shaft H2 to berotated counterclockwise as viewed-from the right end, thereby rotatingshaft I54 clockwise as viewed from the bottom. The gear- 58 and disc 58are thereby driven counterclockwise as viewed in Figure 5. This motioncontinues until the circuit is broken by the movementof contact 48 tothe dead spot between the two contacts 68 and 62.

Energization of relay winding 282 causes switch arm 2I0 to engage afront contact2I2, thereby completing a circuit for energizing theelectromagnet I 48 so. as to release brake I41. This circuit may betracedfrom the upper terminal of battery I88 thru switch I84, conductorI94, switch finger I 18, contact I82, conductor 206, a conductor 2I4,switch arm 2I8, contact 2I2, a, conductor 2 I 6, electromagnet I48 toground and thru ground connection I 92 to the lower terminal of batteryI88.

As soon as the disc 56 has reached the angular position in which theswitch finger 48 lies between the contacts 60 and 62, then the cam shaftI I2 has been moved to an angular position corresponding to that ofcontrol lever I8, and the cams have operated their respective controldevices to the operatin conditions which are best for that position ofthe control lever I8.

If the control shaft I2 and the cam shaft II2 are displaced so thatswitch finger 48 engages contact 62 then the clockwise winding of motorI32 is energized thru a circuitwhich may be traced from the upperterminal of battery I88 thru switch I84, conductor I94, switch fingerI18, contact I82, conductor 208, relay winding 202, conductor 284,switch finger 48, contact 62, a conductor 2 I 8, a conductor 228, abrush, slip ring I44, the clockwise winding on stator I34, slip ring I43, and ground connections I99 and I92 to the lower terminal of batteryI88. This causes operation of disc 56 in a clockwise direction as viewedin Figure 5 until the contacts 48 and 62 are separated,

When theangular position of cam shaft II2 correspondsto that of shaftI2, the contact finger 148:1ies between'the contacts 60 and v82 and the.relay winding 202 is then de-energized. The

switcharm'2I0 then engages a back contact 222, and the energizingcircuit for the brake releasing .electromagnet I48 is interrupted at thecontact 2I2. The stator I34 is therefore locked against rotation.Furthermore, a circuit is completed which places the motor windingsunder the control of the contact 46, which is positioned by the shaftI-2,- and the contacts 53 and 54, which are positioned concurrently withthe throttle arm 20.

If the angular position of throttle arm 28 is then displaced in aclockwise direction, as viewed from the right end, from the positionshown'in Figure 1, so that contact finger 46 engages contact 54, acircuit is completed for energizing motor I32 to drive the hub 52 andthrottle arm 20 ina counterclockwise direction until the contacts 48 and54 are separated. This circuit may be traced fromthe up er terminal ofbattery I88 210, contact 222, switch I86, a conductor 224, contact 46,contact 54, a conductor 226, conductor 220, .a brush, slip rin I44, theclockwise winding on stator I34, slip ring I43 and ground connectionsI99 and I92 to the lower terminal of battery I88. Energization of thiswinding of motor I32 causes shaft I28 to turn clockwise as viewed fromthe right in Figure 1, thereby drivin gear I I4 and sleeve 12counterclockwise as viewed from the right. This counterclockwise motionis transmitted thru link 16 to hub 52. On the other hand if the relativeangular position of shaft I2 and hub 52 is such that contact 46 engagescontact 53, then the motor energizing circuit proceeds as previouslytraced to the contact 46 and then thru contact 53, conductors 208 andI98, a brush, and slip ring I44 to the counterclockwise winding of motorI32. This causes operation of throttle arm 20 thru the linkagepreviously traced, in a clockwise direction as viewed from the rightend.

If it is desired to operate the throttle to maintain a constant value ofintake manifold pressure, the selector switch I86 is operated to thedotted line position shown in the drawing. Under these conditions, theoperation is the same as under semi-automatic conditions except that thethrottle is under the control of the bellows 38.

If the intake manifold pressure increases, bellows 38 collapses causingengagement of contacts 34 and 36. This completes an energizing circuitfor the counterclockwise winding of motor I32, This circuit may betraced from the upper terminal of battery I88 thru switch I84, conductorI84, switch finger I18, contact I82, conductors 288 and 2I4, switch arm218, contact 222, switch I86, contact 228, a conductor 238, contacts 36and 34, a limit switch 23 I, a conductor 232, conductors 288 and I98,-abrush, slip ring I42, the counterclockwise winding of motor I32, slipring I 43 and ground connections I99 and I92 to the lower terminal ofbattery I88. The throttle arm 20 is thereby moved in a direction toclose the throttle, thereby decreasing the intake manifold pressure tothe value selected by manipulation of control lever I8.

If the intake manifold pressure decreases below the selected value, thebellows 38 expands, causing engagement of contacts 32 and 36 andcompletin an energizing circuit for the clockwise winding of motor I32.This circuit may be traced along the circuit last traced to contact 36and then thru contact 32, a limit switch 233, a conductor 234, aconductor 220, a brush, slip ring I44, the clockwise winding of motorI32, slip ring I43, and ground connections I99 and I92 to the lowerterminal of battery I88. This causes operation of the throttle arm 20 ina throttle opening direction, thereby increasing the intake manifoldpressure to restore it to its previously selected value. The limitswitches 23l and' 233 are positioned adjacent the throttle operatingmechanism so as to be opened when the throttle moves to its closed andopen positions, respectively.

From the foregoing, it may be seen that when the system is in manualoperation, all the various control levers are separately movable. Ifdesired, the spark timing and mixture control levers may be mechanicallyinterlocked, so that the mixture control lever may not be moved to alean position without advancing the spark at the same time. If desired,a gated interlock may be used so that it may be overridden inemergencies.

When the system is in semi-automatic operation, all the levers act asfollowers to the main manual control lever l0. When the system is inautomatic operation, the throttle is controlled to maintain a constantintake manifold pressure and the other levers are positioned tocorrespond with the particular value of manifold pressure selected bythe position of lever [0. When such devices are provided, the system mayalso be used to control the waste gate of a turbo-supercharger, or thegear shift of an engine driven supercharger, to aid the throttle inmaintaining a constant manifold pressure. Such an arrangement is shownin my co-pending application Serial No. 514,022, filed December 13,1943.

In automatic operation, all the pilots levers in the cockpit are alwayslinked to their respective engine controls, and hence their positionsindicate the values at which the respective controls are set.

When the system is shifted from automatic operation to manual operation,all the control levers such as [4, l6 and IS in Figure 1, which are notthereafter manually moved, remain in the position which they had duringautomatic operation. If it is desired to change the position of one ofthe levers while keeping the others under automatic control, this may beaccomplished by placing the system temporarily on manual operation,moving the one lever whose position is to be changed, and then restoringthe system in automatic operation. The one lever which was moved willnot then be picked up by its clutch until the automatic system calls fora movement of that lever to the position to which it has been set.

There is illustrated in Figure 6 a series of curves illustrating thevariation of manifold pressure, propeller speed, brake mean effectivepressure and brake horse power with the quantity of air flowing to theengine for combustion purposes. These curves may be used as a basis forthe design of the cam H and the cam groove 24 (see Figure 1) whichdetermine the relationship between manifold pressure and motor speed forany given position of the control lever H]. In any given engine, thespeed of the engine in revolutions per minute and the manifold pressuredetermine the air flow. The curves of Figure 6 are illustrative of therelationship obtained in an engine of 3350 cubic inches displacement.The engine speed and the manifold pressure also determine the brake meaneffective pressure and the brake horse power, since those quantities,for a given 10 engine, can be varied only by varying the engine speed orthe manifold pressure.

In Figures 6 and 7, the range of air flows from 0 to 4000 lbs. per hourhas been designated the idle range, the range between 4000 to 5300 lbs.per hour is called the warm-up range, the range from 5300 to 9600 lbs.per hour is the cruising range, the range from 9600 to 14,200 is theclimbing range, and the range from 14,200 to 16,000 lbs. is the take-offor maximum power range.

It has been found desirable to select the propeller pitch for maximumpropeller efficiency during the climbing and take off ranges of engineoperation and to select the propeller pitch and manifold pressure formaximum engine efficiency during the cruising range. It has been foundthat the most efficient propeller operation is obtained when thepropeller power output varies as the cube of its speed. The relationshipbetween brake mean effective pressure, propeller speed, manifoldpressure and air flow for a maximum propeller efliciency is illustratedby the curves appearing in Figure 6 in full lines thru the climbing andtake off ranges and in dotted lines thru the warm-up and cruisingranges. The curves appearing in full lines thru the warm-up and cruisingranges illustrate the conditions which provide best engine efficiency,and hence best fuel economy. It has been found that the fuel economyoccasioned by the gain in engine efficiency obtainable during thecruising range is greater than the loss in propeller efiiciencyoccasioned by the departure of the propeller speed and powerrelationship which gives maximum propeller efficiency. The gain inengine efliciency results in an increased range of the aircraft.

It is indicated in Figures 6 and 7 that the semi-automatic mode ofoperation corresponds to the idle range and that the automatic modecorresponds to the higher air flow ranges. This is meant to indicate therange in which the respective modes of operation are normally used. Thesemi-automatic mode of operation may be used at any air flow. The fullautomatic mode of operation, however, may not be used at air flows inthe idle range, because of a phenomenon known as boost reversal,

f/Boost reversal is the name applied to a change in the normal variationof intake manifold pressure with engine speed, which takes place undercertain conditions. In most types of internal combustion engines, theintake manifold pressure decreases with an increase in engine speed, ifthe throttle position and other factors affecting the intake manifoldpressure remain constant. Also, the manifold pressure usually increasesas the throttle is moved toward open position. In some engines, however,at slow speeds, this normal state of affairs is reversed so that theintake manifold pressure increases as the throttle moves toward closedposition. The reason for this phenomenon is that the engine intakevalves on high speed engines are set to open before the engine hascompleted its exhaust stroke. When the engine is running fast, theinertia of the gases in the cylinder and the manifolds is suflicient toprevent any exhaust gas from passing out through the intake valve whenit first opens. At low speeds, however, some of the burned gases in theengine cylinder pass out through the intake valve and into-the intakemanifold, causing arr-increase in the pressure there. i

Since the presentsystem, when using the automatic modeofoperatiomresponds to an'increased manifold pressure by a closingmovement of the throttle, it may be seen that if the automatic controlwere used under conditions wherea -boost reversal might take place, theoccurrence of that phenomenon would result ina complete closing of thethrottle. It is therefore necessary that the present system be operatedaccording to the semi-automatic mode, instead of the'full .automatic,through the idle range. If desired, an interlock may be arrangedbetweenthe engine speed governor lever I8 and the. selector switch I86,so that whenever the engine speed is lower. than the value at whichboost reversal occurs, for. example 900 R. P. M., the switch I86 ismoved ,togthe semi-automatic position.

Figure 8 illustrates such an interlocking rrangement. A link25fl,pivotallyattached to the end of arm I8, is provided with. a lug 252which engages a pin 254 which is inserted in a socket in the end of anarm 256. A spring'25B in the socket biases the pin 254 outwardly into.engagement With the link 250 or lug 252. The.:arm.256 is pivoted at 260,and its range of .movement is limited by a pair of stops 252%1'1612254.A link 26B is pivotally attached to the arm 256 near its center, and atits opposite end carries a pin 268 which extends into a slot 21-0 in aplate 212 which is pivotally mounted at 214. The plate 212 carries aswitch I86, which is the same-as-switchIBB of Figure 1. The position ofswitch-I86 determines whether the system is operated in thesemiautomatic -mode or'the automatic mode. The plate2I2 and switchI86-may also'be operated by means of a manual knob 216.

The propeller pitch governor control arm I8 is moved in a clockwisedirection, as viewed in Figure 8, to decrease the engine speed. When apredetermined speed settingis reached, the lug 252 engages pin 254, andcauses rotation of arm 256 in a clockwise direction. Theclockwisemovement of arm 256 does not initially afiect the position ofswitch I86. As soon as the arm 256 passes its vertical position, thespring 258pushes the pin 2,54 outwardly, and causes the arm 256 to snapover against the stop ,264. When this snap action takes place, the.pin,268 engages the end of slot 210 and rotates plate 212 clockwise,moving the switch arm I86 from engagement with contact 228 to contact229. This changesthe sys tem from the automatic mode of operation to thesemi-automatic.

In Figure 7 there are illustrated curves which may be made the basis forthe design of cams setting the carburetor air temperature, ignitiontiming, and fuel to air ratio controls with respect to the manifoldpressure and air flow. The advance of the spark and the lean fuel to airratio during the cruising range are provided in the interest of economy.The richer mixture and less advanced spark in the climbing and take offranges are provided to secure better ngine cooling conditions.

There is shown in Figure 19 an extension of shaft I2 on which aremounted an arm I3 connected to a torque balancing flap control and anarm I5 connected to a carburetor air temperature control.

The carburetor air temperature is decreased with increased air flow, asshown in Figure 7, in order to take advantage of the increased airdensity at the lower temperature and hence the increased mass of airwhich can be introduced in the engine cylinders at each stroke.

In addition to the conditions specifically illustrated in Figure 1, thisapparatus may be used to-control other conditions relating to thefunctioning of an aircraft. For example, as shown in Figure 9, it mightbe used to regulate torque balancing flaps. By positioning such 'flapsas a function of the engine horse power, the tendency of the reaction ofthe propeller to twist the plane may be overcome. Furthermore, flaps maybe provided to correct the tendency of the aircraft to climb or dive'dueto the changes in the longitudinal thrust. In rotary wingedaircraft, the torque balancing may be performed by means other thanflaps, but it still may be regulated as a function of l the horse poweroutput of l the engines.

While I have shown and described a preferred embodiment of my invention,other modifications thereof will readily occur to those skilled in theart, and I intend my invention to be limited only by the appendedclaims.

I claim as my invention:

1. Control apparatus for an internal combustionengine, comprisingthrottle means for controlling-the flow of air to said engine forcombustion purposes, a manually movable control member, motor means,first clutch means operable to connect said throttle means and saidcontrol member, second clutch means operable to connect said throttlemeans and said motor means, operating means for both said clutch meansmovable between a first position wherein said first clutch means may beengaged and said second clutch means is disengaged and a second positionwherein said first clutch means is disengaged and said second clutchmeans may be engaged, means biasing said clutch operating means to saidfirst position, means for locking said clutch operating means in saidsecond position,'a-worm driven by saidmotor means, a sector worm wheelconnected to said clutch operating means for movement therewith andadapted-to be driven by said worm, means responsive toa-condition-indicative of the need for operation of said throttle means,and means for transferring control of said throttle means from saidcontrol member to said condition responsive means,.said last-named meansincluding means for initiating operation of said motor in a direction todrive said clutch operating means thru said worm and sector worm wheeltoward said second position, and means efiective upon movement of saidclutch operating means to said second position to operate said lockingmeans andto place said condition responsive means in control of saidmotor means.

2. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air "to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, motor means, firstmotion-transmitting means, including first clutch means, operable toconnect said motor means and said control device, secondmotion-transmitting means, including second clutch means, operable toconnect said motor means and said throttle means, third clutch meansoperable to connect said throttle means and said member, operating meansfor all said clutch means movable between a first position wherein saidthird clutch means may be engaged and said first and second clutch meansare disengaged and a second position wherein said third clutch means isdisengaged and said first .and second clutch means may be engaged, means13 biasing said clutch operating means to said first position, means forlocking said clutch operating means in said second position, a Wormdriven by said motor means, a sector worm wheel connected to said clutchoperating means for simultaneous movement therewith and adapted to bedriven by said Worm, means responsive to the relative positions of saidcontrol member and said control device, means responsive to a conditionindicative of the need for operation of said throttle means, and meansoperable to transfer control of said throttle means from said controlmember to said condition responsive means and to position said controldevice, said last-named means including means for initiating operationof said motor in a direction to drive said clutch operating means thrusaid Worm and sector Worm wheel toward said second position, meansefiective upon movement of said clutch operating means to said secondposition to operate said locking means, to place said motor means undercontrol of said position responsive means to drive said control devicethru said first motion-transmitting means to a position corresponding tothat of said control member, and means eiTective upon movement of saiddevice to said corresponding position to place said motor means undercontrol of said condition responsive means to drive said throttle meansthru said second motion-transmitting means.

3. Control apparatus for an internal combustion engine, comprisingthrottle means for con trolling the flow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, a manually movable controlmember, motor means, control means responsive to a condition indicativeof the need for operation of said throttle means, and means operableselectively: (1) to connect said member and said throttle means, (2) toplace said condition responsive means in control of said motor means andto connect said throttle means to said motor means, or (3) to place saidcontrol member in control of said motor means and to connect saidcontrol device to said motor means.

4. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, a manually movable control member, motor means,control means responsive to a condition indicative of the need for operation of said throttle means, and means operable selectively: (l) toconnect said member and said throttle means, (2) to place said conditionresponsive means in control of said motor means and to connect saidthrottle means to said motor means, or (3) to place said control memberin control of said motor means and to connect said throttle means tosaid motor means.

5. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, a manually movable controlmember, motor means, control means responsive to a condition indicativeof the need for operation of said throttle means, and means operableselectively: (1) to connect said member and said throttle means, (2) toplace said condition responsive means in control of said motor means andto connect said throttle means to said motor means, (3) to place saidcontrol member in control of said motor means and to connect said 14control device to said motor means, or (4) to place said control memberin control of said motor means and to connect said throttle means tosaid motor means.

6. Control apparatus including a pair of load devices to be positioned,electrical motor means for positioning said devices including a pair ofconcentric relatively movable members, electrical Winding means on atleast one of said members adapted to cause a reaction of said membersrelative to each other upon energization thereof, means normallyefiective to lock one of said members against rotation, means operableto connect each of said members to one of said load devices, a pair ofelectrical circuits for energizing said winding means, means forcontrolling the energization of one of said circuits in accordance witha condition indicative of the need for operation of the load deviceconnected to said one member, means responsive to the flow of current insaid one circuit to release said locking means and to interrupt theother of said circuits, and means in said other circuit for controllingthe energization thereof in accordance with a condition indicative ofthe need for operation of the other of said load devices.

'7. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, a manually movable controlmember, motor means, control means responsive to a condition indicativeof the need for operation of said throttle means and eliective toproduce selectively opposite control effects in accordance with thedirection of departure of said condition from a predetermined value,means for adjusting said control means to select said value, aconnection between said adjusting means and said control member, andmeans operable selectively: (1) to connect said member and said throttlemeans, (2) to place said condition responsive means in control of saidmotor means and to connect said throttle means to said motor means, (3)to place said control member in control of said motor means and toconnect said control device to said motor means, or (4) to place saidcontrol member in control of said motor means and to connect saidthrottle means to said motor means.

8. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of en'- gine operation, a manually movablecontrol mem- 4 her, a single motor, control means responsive to 'acondition indicative of the need for operation 9. Control apparatus foran internal combus tion engine, comprising throttle means forcontrolling the fiovv of air to said enginefor com bustion purposes, acontrol device movable to control the setting of the propeller pitchgovernor, a manually movable control member, a

single motor,- control-meansresponsive to a pressure conditionindicative of the need for opera tion of said throttle means, and meansoperable selectively: (1) to connect said member and said throttlemeans, (2) to place said condition responsive means in control of saidmotor and to connect said throttle means to said motor, (3) to placesaid control member in control of said motor and'to connect said controldeviceto said motor, or (4) to place said control member in control ofsaid motor and to connect said throttle means to said motor.

10. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the fiow of air to said engine forcombustion purposes, a plurality of control devices, each movable toestablish the value of a difierent condition of engine operation, amanually movable control member, a single electrical motor including apair of concentric relatively movable membersand electrical windingmeans on at least one of said motor members adapted to cause a reactionof said motor members relative to each other upon energization thereof,means normally effective to lock one of said motor members againstrotation, a connection between said one motor member and said devices, aconnection between the other of said motor members and said throttlemeans, first clutch means operable to connect said throttle means andsaid control member, second clutch means in the connection between saidcontrol devices and said one motor member, third clutch means in theconnection between said throttle means and the other of said motormembers, operating means for all said clutch means movable between afirst position wherein said first clutch means may be engaged and saidsecond and third clutch means are disengaged and a second positionwherein said first clutch means is disengaged and said second and thirdclutch means may be engaged; means biasing said op erating means to saidfirst position, means for holding said operating means in said secondposition, a worm driven by said other motor member, a sector worm Wheelconnected to said clutch operating means for movement therewith andadapted to engage said worm, first double-throw switch means, means fornormally holding said switch means in a first circuit-closing positionand operative as an incident to movement of said operating means to itssecond position to move said switch means to a second circuit-closingposition, second double-throw switch means responsive to the pressure inthe intake manifold of said engine and movable to its respectivecircuit-closingpositions in accordance with the direction of departureof said pressure from a predetermined value, adjusting means forselecting said value and connected to said manual control member for.movement therewith, third double-throw switch means movable to itsrespective circuitclosing positions in accordance with the direction ofdisplacement of said throttle means from a position corresponding tothat of said control member, fourth double-throw switch means movable toits respective circuit-closing positions in accordance with thedirection of displacement of said control devices from positionscorresponding to the position of said control member, first electricalcircuit means for controlling the energization of said winding meansincluding said first switch means when the latter is in its firstcircuitclosing position, said first electrical circuit means beingefiectiveon completion to cause operation of said-,other-motor member todrive said clutch operating means to said second position and therebymove said first switch means to its secend position, second electricalcircuit means for controlling the energization of. said winding meansincluding said first switch means when the latter is in its secondposition and said second.

switch means, third electrical circuit meansfor controlling theenergization of saidv winding means including said first switch meanswhen the, latter is in its second position and said'third' switch means,fourth electrical circuit means for controlling the energization of saidwinding means including said first switch means when the latter is inits secondposition and said fourth.

switch means, means responsive to the current flow in said fourthcircuit means for releasing said locking means and for interrupting saidsecond and third circuit means, and selector switch means forselectively connecting said second and third circuit means to saidwinding means.

11. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling thefiow of air to said engine forcombustion purposes, a plurality of control devices, each bers relativeto each other upon energization thereof, means normally efiective tolock one of said motor members against rotation, a connection betweensaid'one member and said cam operating means, a connection between theother of said members and said throttle means, first clutch meansoperable to connect said throttle means and said control member,second'clutch means in the connection between said control devices andsaid one motor member, third clutch means in the connection between saidthrottle means and the other of said motor members, op-

erating means for all said clutch means movablebetween a first positionwherein said first clutch means may be engaged and said second and thirdclutch means are disengaged and a second position wherein said firstclutch means is disengaged and said second and third clutch means may beengaged, means biasing said operating means to said first position,means for holding said operating means in said second position, a wormdriven by said other motor member, a sector worm wheel connected to saidclutch operating means for movement therewith and adapted to engage saidworm, first double-throw switch means, means for normally holding saidswitch means in afirst' circuit-closing position and operative as anincident to movement cf'said operating means to its second position tomove said switch means to a second circuit-closing position, seconddoublethrow switch means responsive to the pressure in the intakemanifold of said engine and movable to its respective circuit-closingpositions in ac cordance with the direction of departure of saidpressure fro-m a predetermined value, adjusting means for selecting saidvalue and connected to said manuallcontrol member for movementtherewith, third double-throw switch means movable to its respectivecircuit-closing positions in accordance with,the direction ofdisplacement of said throttle. means from a position corresponding tothat of said control member, fourth doublethrow switch means movable toits respective circuit-closing positions in accordance with thedirection of displacement of said control devices from positionscorresponding to the position of said control member, first electricalcircuit means for controlling the energization of said winding meansincluding said first switch means when the latter is in its firstcircuit-closing position, said first electrical circuit means beingeffective on completion to cause operation of said other motor member todrive said clutch operating means to said second position and therebymove said first switch means to its second position, second electricalcircuit means for controlling the energization of said winding meansincluding said first switch means when the latter is in its secondposition and said second switch means, third electrical circuit meansfor controlling the energization of said winding means including saidfirst switch means when the latter is in its second position and saidthird switch means, fourth electrical circuit means for controlling theenergization of said winding means including said first switch meanswhen the latter is in its second position and said fourth switch means,means responsive to the current flow in said fourth circuit means forreleasing said locking means and for interrupting said second and thirdcircuit means, and selector switch means for selectively connecting saidsecond and third circuit means to said winding means.

12. Control apparatus comprising an element to be moved between a safeposition and an active position, means biasing said element toward saidsafe position, motor means for driving said element to said activeposition, a worm connected to said motor means, a sector worm wheelconnected to said element, said sector wheel having a first positioncorresponding to the safe position of said element wherein said wheelengages said worm and a second position corresponding to the activeposition of said element wherein said wheel is free from said worm, saidfirst and second positions being separated by more than 180 on theperiphery of said wheel, means operative when said wheel is driven bysaid worm to the end of said sector to move said wheel additionallyuntil said second position is reached, and means operable to lock saidelement in said active position.

13. Control apparatus including a pair of load devices to be positioned,electrical motor means for positioning said devices including a pair ofconcentric relatively movable members, electrical winding means on atleast one of said members adapted to cause a reaction of said membersrelative to each other upon energization thereof, brake means to lockone of said members against rotation, means biasing said brake means toa position wherein said one member is locked, electrical means operativewhen energized to release said brake means, means operable to connecteach of said members to one of said load devices, a pair of electricalcircuits for energizing said winding means, means in one of saidcircuits for controlling the energization thereof in accordance with acondition indicative of the need for operation of the load deviceconnected thereto, a pair of contacts connected in said other circuit, arelay winding connected in said one circuit, switch means controlled bysaid relay winding and eifective upon energization thereof to completean energizing circuit for said brake releasing means and to open saidcontacts, said switch means 18 being effective upon de-energization ofsaid winding to close said contacts, and means in said other circuit forcontrolling the energization thereof in accordance with a conditionindicative of the need for operation of the other of said load devices.

14. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, a plurality of control devices, each movable toestablish the value of a different condition of engine operation, cammeans for moving each of said devices, means for operating all said cammeans simultaneously to maintain a predetermined relationship betweensaid conditions, a manually movable control member, motor means, controlmeans responsive to a condition indicative of the need for operation ofsaid throttle means, and means operable selectively: (1) to connect saidmember and said throttle means, (2) to place said condition responsivemeans in control of said motor means and to connect said throttle meansto said motor means, or (3) V to place said control member in control ofsaid motor and to connect said cam operating means to said motor means.

15. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the fiow of air to said engine forcombustion purposes, a plurality of control devices, each movable toestablish the value of a difierent condition of engine operation, cammeans for moving each of said devices, means for operating all said cammeans simultaneously to maintain a predetermined relationship betweensaid conditions, a manually movable control member, first and secondmotor means, control means responsive to a condition indicative of theneed for operation of said throttle means and efiective to produceselectively opposite control effects in accordance with the direction ofdeparture of said condition from a predetermined value, meansforadjusting said control means to select said value, a connection betweensaid adjusting means and said control member, mean to place saidcondition responsive means in control of said first motor means and toconnect said throttle means to said first motor means, and means toplace said control member in control of said second motor means and toconnect said cam operating means to said motor means.

16. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the fiow of air to said engine forcombustion purposes, first motor means for driving said throttle means,a plurality of control devices, each movable to establish the value of adifferent condition of engine operation, means for pcsitioning saidcontrol devices simultaneously to maintain predetermined relationshipsbetween said conditions, second motor means for driving said positioningmeans, control means responsive to the pressure in the intake manifoldof said engine and effective to produce selectively opposite controleffects in accordance with the direction of departure of said pressurefrom a predetermined value, means including a manually movable memberfor adjusting said control means to select said value, means to placesaid pressure responsive means in control of said first motor means andmeans to place said manually movable member in control of said secondmotor means.

17. Control apparatus comprising an element to be moved between a safeposition and an active position, meansbiasing said element toward saidsafe position, motor means for driving aid element to said activeposition, a worm connected to said motor means, a sector worm wheelconnected to said element, said sector wheel having a first positioncorresponding to the safe position of said element wherein said wormengages one extremity of said sector and a second position correspondingto the active position of said element wherein said wheel is free fromsaid worm, means responsive to the angular position of said wheel forcausing rotation of said motor means in a direction such that said wormdrives said wheel thru said sector, means operative as an incident tooperation of said wheel by said worm to the end of said sector to movesaid wheel additionally until said second position is reached, and meansoperable to lock said element in said active position.

18. Clutch means comprising a driving memher and a driven member havingaligned apertures and rotatable about an axis extending thru saidapertures, said members also having radial apertures axially aligned, ashaft extending thru said axial apertures and having a cam surfacealigned axially with said radial apertures, a key reciprocable in theradial apertures of one of said members, spring means for holding saidkey in contact with said cam surface so that upon rotation of said shaftsaid key is reciprocated in its associated radial aperture by the camsurface, and an extension on said key extending parallel to said shaft,the other of said members having a generallyarcuate surface axiallyaligned with said extension and a notch in said surface adapted toreceive said extension, so that when said notch is aligned with saidextension and said shaft is turned to permit engagement of saidextension and said notch, said members are locked together.

19. Clutch means comprising a driving member, a driven member, a shaftextending thru said members and forming a pivot for said members, a keycarried by one of said members and movable radially with respect to saidone member, cam means on said shaft for reciprocating said key, and anextension on said key extending parallel to said shaft, the other ofsaid members having a generally arcuate surface axially aligned withsaid extension and a notch in said surface adapted to receive saidextension, so that when said notch is aligned with said extension andsaid cam means is turned to permit engagement of ,said extension andsaid notch, said members are locked together.

20.'Control apparatus comprising motor means, a plurality of loaddevices to be selectively connected to said motor means, a clutchoperating shaft, a clutch for connectin each of said load devices tosaid motor means, each of said clutches comprising a driving member anda driven member pivotally mounted on said shaft, a key carried by one ofsaid members and movable radially with respect to said one member, cammeans on said shaft for reciprocating said key, and an extension on saidkey extendingparallel to said shaft, the other of said members having agenerally arcuate surface axially aligned with said extension and anotch in said surface adapted to receive said extension, so that whensaid notch is aligned with said extension and said cam means is turnedto permit engagement of said extension and said notch, said members arelocked together and means for drivingly connecting said motor means andsaid shaft.

21. Control apparatus comprising motor means,

a driving member connected to said motor, a driven member, a shaftextending thru said members and forming a pivot for said members, a keycarried by one of said members and movable radially with respect to saidone member, cam means on said shaft for reciprocating said key, and anextension on said key extending parallel to said shaft, the other ofsaid members having a generally arcuate surface axially with saidextension and a notch in said surface adapted to receive said extension,so that when said notch is aligned with said extension and said cammeans is turned to permit engagement of said extension and said notch,said members are locked together and means for drivingly connecting saidmotor means and said shaft to operate said cam means to a positionpermitting engagement of said extension and said notch, said motor meansbeing effective thereafter to rotate said driving member until saidextension and said notch are alined.

22. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, a manually movable control member, motor means,control means responsive to a condition indicative of the need foroperation of said throttle means, and means operable selectively: (l) toplace said condition responsive means in control of said motor means andto connect said throttle means to said motor means, or (2) to place saidcontrol member in control of said motor means and to connect saidthrottle means to said motor means.

23. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, a manually movable controlmember, motor means, control means responsive to a condition indicativeof the need for operation of said throttle means, and means operableselectively: (1) to place said condition responsive means in control ofsaid motor means and to connect said throttle means to said motor means,or (2) to place said control member in control of said motor means andto connect said control device to said motor means.

24. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, a manually movable controlmember, motor means, and means operable-selectively: (1) to place saidcontrol member in control of said motor means and to connect saidcontrol device to said motor means, or (2) to place said control memberin control of said motor means and to connect said throttle means tosaid motor means.

25. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, first motor means for driving said throttle means,a plurality of control devices, each movable to establish the value of adifferent condition of engine operation, means for positioning saidcontrol devices simultaneously to maintain predetermined relationshipsbetween said conditions, second motor means for driving said positioningmeans, control means responsive to a condition indicative of the needfor operation of said throttle means and effective to produceselectively opposite control effects in accordance with the direction ofdeparture of said condition from a predetermined value, means includinga manually movable member for adjusting said control means to selectsaid value, means to place said pressure responsive means in control ofsaid first motor means and means to place said manually movable memberin control of said second motor means.

26. Control apparatus comprising motor means, a rotatable driving memberconnected to said motor means, a rotatable driven member, a clutchmember mounted on one of said rotatable members for rotation therewith,said clutch member being movable with respect to said one member toengage the other of said members to transmit motion thereto, means onsaid other member to prevent efiective engagement thereof by said clutchmember except when said rotatable members are at predetermined relativeangular positions, operating means for said clutch member movablebetween a first position wherein said clutch member is disengaged fromsaid other member and a second position wherein said clutch member tendsto engage said other member, a driving connection between said motormeans and said operating means, and means for controlling said motormeans to first drive said operating means to said second position andthereafter to drive said driving member until said members attain saidpredetermined relative angular positions whereupon said clutch memberoperatively engages said other rotatable member.

2'7. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, motor means, firstmotion-transmitting means, including first clutch means, operable toconnect said motor means and said control device, secondmotion-transmittin means, including second clutch means, operable toconnect said motor means and said throttle means, third clutch meansoperable to connect said throttle means aid said member, and operatingmeans for all said clutch means movable between a first position whereinsaid third clutch means may be engaged and said first and second clutchmeans are disengaged and a second position wherein said third clutchmeans is disengaged and said first and second clutch means may beengaged.

28. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, a manually movable controlmember, motor means, control means responsive to the pressure in theintake manifold of said engine, and means operable selectively: (l) toplace said pressure responsive means in control of said motor means andto connect said throttle means to said motor means, or (2) to place saidcontrol member in control of said motor means and to connect saidcontrol device to said motor means.

29. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the fiow of air to said engine forcombustion purposes, at least one control device movable to establishthe value of a condition of engine operation, a manually movable controlmember, motor means, control means responsive to the rate of flow ofcombustion air to said engine,

and means operable selectively: (1) to place said air flow responsivemeans in control of said motor means and to connect said throttle meansto said motor means, or (2) to place said control member in control ofsaid motor means and to connect said control device to said motor means.

30. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the fiow of air to said engine forcombustion purposes, a manually movable control member, motor means fordriving said throttle means, control means responsive to the pressure inthe intake manifold of said engine, and means indicative of the speed ofsaid engine to place said condition responsive means in control of saidmotor means when said speed is above a predetermined value, and toplacersaid control member in control of said motor means when said speedis below said value.

31. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, first motor means for driving said throttle means,control means responsive to a condition indicative of the power outputof said engine and effective to produce selectively opposite controleffects in accordance with the direction of departure of said conditionfrom a predetermined value, means including a manually movable memberfor adjusting said control means to select said value, means includingsaid condition responsive means for controlling said first motor meansto maintain said selected value, a first control device movable toestablish the ignition timing of said engine, a second control devicemovable to establish the ratio of fuel-to-air supplied to said engine,cam means for positioning said control devices simultaneously, secondmotor means for driving said positioning means, and means responsive tothe position of said manually movable member for controlling said secondmotor means to cause a following movement of said cam means for eachmovement of said member, said cam means being contoured to operate saidcontrol devices to produce advanced ignition timing and a leanfuel-to-air ratio at intermediate values of engine power output, andretarded ignition timing and a rich fuel-to-air ratio at high values ofengine power output.

32. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the fiow of air to said engine forcombustiOn purposes, first motor means for driving said throttle means,control means responsive to a condition indicative of the power outputof said engine and eifective to produce selectively opposite controlefiects in accordance with the direction of departure of said-conditionfrom a predetermined value, means including a manually movable memberfor adjusting said control means to select said value, means includingsaid condition responsive means for controlling said first motor meansto maintain said selected value, means for controlling the temperatureof the combustion air supplied to said engine, a control device movableto establish the value of combustion air temperature maintained by saidcontrol means, cam means for positioning said control device, secondmotor means for driving said positioning means, and means responsive tothe position of said manually movable member for controlling said secondmotor meons to cause a following movement of said cam means for eachmovement of said member, said cam means being contoured to operate saidcontrol device to de- 23 crease the combustion air temperature as thepower output of said engine increases.

33.. Control apparatus for an internal combustion engine, comprisingthrottle means for controlling the flow of air to said engine forcombustion purposes, first motor means for driving said throttle means,control means responsive to the intake manifold pressure of said engineand efiective to produce selectively opposite control effects inaccordance with the direction of departure of said pressure from apredetermined value, means including a manually movable member foradjusting said control means to select said value, first means forcontrolling said first motor means including said condition responsivemeans and effective to cause movement of said throttle in a closingdirection in response to an increase in said pressure, second means forcontrolling said first motor means in response to the position of saidmember and effective to cause movement of said throttle in opening andclosing directions, respectively, in response to movement of saidcontrol member in higher and lower pressure directions, governor meansfor maintaining the speed of said engine substantially constant, meansfor adjusting the speed setting of said governor, second motor means fordriving said adjusting means, means responsive to the position of saidmanually movable member for controlling said second motor means, andmeans associated with said governor for placing said second controlmeans in control of said first motor when said governor is set at aspeed less than said value.

LEIGHTON LEE, II.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS OTHER REFERENCES Ser. No. 281,826, Stieglitz etal. (A. P. C.) pub. May 18, 1943.

